Surgical instrument for deploying a prosthesis

ABSTRACT

The present invention relates to a surgical instrument ( 1 ) for deploying a prosthesis ( 200 ) and includes a first layer and second layer assembled together so as to define an internal space accessible to said surgical instrument ( 1 ) by means of an opening provided in said first layer, said surgical instrument including at least one sheet ( 2 ) made of a flexible resilient material, said sheet continuously overlapping itself one or more times so as to define a plurality of levels forming a spiral ( 3 ). The invention also relates to a kit including such a surgical instrument and such a prosthesis.

The present invention relates to a surgical instrument making itpossible to place a prosthesis, in particular for covering hernias, aswell as a kit comprising this surgical instrument and this prosthesis.

The abdominal wall in humans is made up of fats and muscles connected toeach other by fascias. A break in continuity can occur at the fascias,allowing part of the peritoneum to pass, which then constitutes a sac,or a hernia, containing either fat or part of the intestines. Hernias orincisional hernias (hernia occurring on a surgical parietal scar)manifest themselves by a protuberance on the surface of the skin and arequalified as umbilical or inguinal hernias or incisional hernias, forexample, depending on where they are located.

The most traditional method for repairing a hernia involves placingstressed suture threads. However, this type of repair causes pain forthe patient and, due to the significant stresses, involves anon-negligible risk of tearing of muscles and fascia by the suturesand/or a recurrence of the hernia.

In order to minimize the risks of recurrence, surgeons frequently usethe placement of a synthetic lattice prosthesis that replaces orstrengthens the weakened anatomical tissues without requiring that theedges of the damaged tissues be brought together. However, such aprosthesis is subject to an abdominal pressure that tends to expel ittowards the outside. Yet the effectiveness of the prosthesis, andtherefore the minimization of the risks of recurrence, depend in largepart on the fixing thereof. First, the spreading out of the prostheses,which are often flexible, is difficult, such that they tend to formfolds on the abdominal wall. The absence of complete spreading outcauses a risk of engagement of the peritoneal sac and increases thechances of recurrence. It is therefore crucial for the surgeon to ensurethat no part of the prosthesis is folded and that no viscus or any partof the intestines is inserted between the prosthesis and the abdominalwall. Then, poor positioning of the sutures or poor fixing of theprosthesis risks distorting the latter and creating stresses.

The present invention aims to propose a surgical instrument making itpossible to facilitate the spreading out and fixing of a prosthesis thatcan be used for the surgical treatment of hernias and making it possibleto resolve the aforementioned drawbacks, in particular, but notexclusively, for the surgical treatment of small hernias.

The present invention also relates to a surgical kit for the treatmentof a hernia of the abdominal wall.

In the present application, “prosthesis” refers to a biocompatiblemedical device that can be implanted in the human or animal body.

A first aspect of the invention relates to a surgical instrument fordeploying a prosthesis intended to fill in a hernial defect of theabdominal wall, said prosthesis including at least one first layer madefrom a biocompatible flexible material intended to be placed oppositethe abdominal wall, and at least one second layer made from abiocompatible flexible material intended to be placed opposite theabdominal cavity, said first and second layers being assembled togetherso as to define an internal space accessible to said surgical instrumentby means of an opening provided in said first layer, said surgicalinstrument including at least one sheet made of a flexible resilientmaterial, said sheet continuously overlapping itself one or more timesso as to define a plurality of levels (or layers) forming a spiral.

Due to the resilience of said sheet, the spiral is able to adopt asubstantially flat configuration, in which each level is in contact withthe adjacent level, corresponding to an idle configuration in which thespiral does not undergo significant stresses, or on the contrary adeployed configuration, in which no level is in contact with anotherlevel, corresponding to a configuration in which a force tending tospace the two ends of the spiral away from each other is exerted. Inthis application, we will also refer to the surgical instrumentaccording to the invention using the terms protective disc, or disc, orspiral.

Owing to the resilience of the material making up said sheet, the discor spiral has a spring effect: thus if, in its flat configuration, it isfolded by pressing it on itself while exerting pressure on its edges, ittends to return naturally to its flat configuration when the exertedpressure is released.

As will appear in the following description, the surgical instrumentaccording to the invention is intended to be introduced into theprosthesis within the internal space thereof, in order to facilitate theintroduction, placement and deployment of the prosthesis in theimplantation site. The surgical instrument must then be removed from theprosthesis once the latter is fixed to the implantation site.

In one embodiment of the invention, the upper end of the spiral (ordisc) comprises a removal tab. Thus, once the prosthesis is correctlydeployed and positioned, then fixed, the surgeon can remove the surgicalinstrument or disc from the prosthesis by pulling on the removal tab: hethen deploys the disc, which extends in the form of a spiral, and thesurgeon can then easily remove the disc by causing it to rotate arounditself, or more easily by exerting a simple upward linear traction onthe tab: given its shape and material, preferably having a low frictioncoefficient relative to the prosthesis, the spiral unwindsautomatically.

In one embodiment of the invention, the material making up said sheet isa polymer chosen from polypropylene, polyethylene,polytetrafluoroethylene (PTFE), and/or mixtures thereof, for examplehaving a low friction coefficient with the prosthesis to facilitate theremoval thereof.

The present invention also relates to a surgical kit for treating ahernia of the abdominal wall comprising:

a surgical instrument as described above;

and a prosthesis intended to fill in said defect, said prosthesiscomprising at least one layer of a biocompatible flexible materialintended to be placed opposite the abdominal wall and at least onesecond biocompatible flexible material intended to be placed oppositethe abdominal cavity, said first and second layers being assembled toeach other so as to define an open inner space using an opening formedin said first layer.

In one embodiment, the surgical kit according to the invention includesa plurality of centering threads intended to be connected to saidprosthesis around the perimeter of said opening. It is understood thatthe centering threads can be fixed to the prosthesis beforehand or thatsaid centering threads could be fixed later by the surgeon and/orremoved at the end of the operation.

In one embodiment of the surgical kit, at least one of the layers ofsaid prosthesis is made up of an arrangement of threads. Preferably,both layers are made up of an arrangement of threads.

In one embodiment of the invention, the second layer of said prosthesisof the kit is covered with an anti-adhesive coating on its face intendedto be placed opposite the abdominal cavity.

Within the meaning of this application, “anti-adhesive” refers to asmooth and non-porous biocompatible material or coating not offering anyroom for cellular recolonization.

The anti-adhesive coating according to the present invention makes itpossible to protect, at least during the initial scarring phase, thesecond layer of said prosthesis, i.e. it is not exposed to inflammatorycells, such as granulocytes, monocytes, macrophages, or multinucleargiant cells generally activated by the surgery. Indeed, at least duringthe initial scarring phase, the length of which can vary from about 5 to10 days, only the anti-adhesive coating is accessible by the differentfactors such as proteins, enzymes, cytokines, or inflammatory linecells, at the first textile portion.

In the event the anti-adhesive coating is made up of non-resorbablematerials, it thus protects the coated prosthesis layer before and afterimplantation, throughout the entire implantation time of the prosthesis.

Moreover, owing to the anti-adhesive coating, the fragile surroundingtissues such as the hollow viscera, for example, are protected, inparticular from the formation of unwanted severe post-surgical fibrousadhesions.

In the event the anti-adhesive material comprises a bioresorbablematerial, it is preferable to choose a bioresorbable material that doesnot resorb until several days have passed so that the anti-adhesivecoating can perform its function of protecting the intestine and thehollow organs during the days following the operation, and, until thecellular rehabilitation of the prosthesis in turn protects the fragileorgans.

Other features and advantages of the invention will appear upon readingthe following description of one particular embodiment, provided solelyas a non-limiting example, in which the prosthesis is a reinforcement ofthe abdominal wall.

FIG. 1 is a cross-sectional view of an abdominal median hernia orincisional hernia;

FIG. 2 is a perspective view of a prosthesis contained in the kitaccording to the present invention;

FIG. 3 is a cross-sectional illustration of the prosthesis of FIG. 2;

FIG. 4 is a cross-sectional diagrammatic illustration of the abdominalwall showing a repair of a hernia that has been done using a surgicalkit according to the present invention;

FIG. 5 is a perspective view of an embodiment of the surgical instrumentaccording to the invention, in its flat configuration;

FIG. 6 is a perspective view of the surgical instrument of FIG. 5, inits deployed configuration;

FIG. 7 is a perspective view of one embodiment of the kit according tothe invention, the surgical instrument being completely introduced intothe inner space of the prosthesis;

FIG. 8 is a diagrammatic cross-sectional illustration of the abdominalwall showing the introduction into the implantation site of the kit ofFIG. 7;

FIG. 9 is a perspective view of the kit of FIG. 7, once redeployed inthe implantation site (the latter not being shown);

FIG. 10 is a perspective view of the step for removing the surgicalinstrument from the prosthesis, once the latter is fixed in theimplantation site (the latter not being shown).

FIG. 1 shows a hernia 100 of the abdominal wall 101 that ischaracterized by a break in the continuity of the fascia 102 surroundingthe rectus muscles 103 and a passage of the peritoneum 104 forming asac, the hernial sac 105, which contains either fat (omentum) or part ofthe viscera 106, and then exerts pressure on the fatty tissues 107 andis flush with the skin 108. Hernia treatment 100 consists of replacingand maintaining the viscera 106 in the abdominal cavity 109.

FIGS. 2 and 3 show a prosthesis 200 able to fill in a hernial defect 100like that shown in FIG. 1, said prosthesis 200 comprising at least onefirst layer 201 of biocompatible flexible material intended to be placedopposite the abdominal wall 101 and at least one second layer 202 ofbiocompatible material intended to be placed opposite the abdominalcavity 109. Said first and second layers (201, 202) are assembled toeach other so as to define an inner space 203 open via an opening 204formed in said first layer 201 and extending to the assembly zone ofsaid first and second layers 201, 202.

In the illustrated example, the first layer 201 and the second layer 202are made up of arrangements of threads, such as tissues, non-wovens orknits, and they are assembled on their periphery by a seam 205. Thethreads forming the layers (201, 202) can be chosen among resorbableand/or non-resorbable threads 206. In the illustrated example, ananti-adhesive coating 206, which is preferably bioresorbable,advantageously covers the outer surface of the second layer 202 in orderto avoid in particular the formation of unwanted severe post-surgicalfibrous adhesions.

The prosthesis 200 of FIGS. 2 and 3 is intended to repair a hernia 100like that of FIG. 1, and must be positioned, after implantation, asshown in FIG. 4. In that figure, the prosthesis 200 is diagrammed, afterreduction of the hernial sac 105, as placed to fill in the hernialdefect 100: as shown in this figure, in which sutures (901; 903) arediagrammed, the surgeon has made an incision in the skin 108 and thefascia 102 to introduce the prosthesis 200 into the hernial defect; hehas then arranged the prosthesis 200, with its first layer 201 oppositethe abdominal wall 101 and its second layer 202 opposite the abdominalcavity 109; he has fixed the prosthesis 200 by suturing the layer 201 tothe fascia 102 and the peritoneum 104 using sutures 903, then he hasclosed the initial incisions of the fascia 102 and the skin 108 usingsutures 901.

During such an operation, the difficulty lies in the introduction anddeployment of the prosthesis 200, in particular its spreading out andplacement against the abdominal wall 101, whereas moreover the initialincisions in the skin 108 and the fascia 102 needing to be as small aspossible, the surgeon's workspace and visibility are particularlylimited.

FIGS. 5 and 6 show an embodiment of a surgical instrument 1 according tothe invention, said instrument 1 being particularly useful for theintroduction and deployment of the prosthesis 200 during the operationdescribed above.

As shown in FIGS. 5 and 6, the surgical instrument 1 according to theinvention comprises at least one sheet 2 made from a flexible andresilient material, said sheet 2 overlapping itself one or severaltimes, continuously, so as to define several layers or levels (a, b, c)forming a spiral 3. As shown in FIG. 6, the spiral 3 is finite (orlimited) and has two opposite ends, an upper end 3 a and a lower end 3b. Due to the resilience of said sheet 2, the spiral 3 can adopt asubstantially flat configuration, in which each level (a, b, c) is incontact with the adjacent level (a, b, c), corresponding to an idleconfiguration in which the spiral 3 does not undergo significantstresses: this configuration is shown in FIG. 5. Alternatively, thespiral 3 can adopt a deployed configuration, in which no level (a, b, c)is in contact with another level, corresponding to a configuration inwhich a force, for example exerted by the surgeon, tending to move thetwo ends (3 a, 3 b) of the spiral 3 away from each other is exerted:this configuration is shown in FIG. 6. The surgical instrument is thuscapable of adopting two configurations: a flat configuration, as shownin FIG. 5, and a deployed configuration, as shown in FIG. 6.

As appears in FIG. 5, in its flat configuration, the spiral 3, due tothe small thickness of the sheet 2, forms a flat disc, provided with acentral hole 3 c.

The material making up said sheet 2 is preferably a polymer of thepolypropylene, polyethylene, or polytetrafluorethylene (PTFE) type; sucha polymer makes it possible to give the sheet the necessary resilienceto go from its flat spiral configuration to its deployed spiralconfiguration. Moreover, as will appear from the continuation of thedescription, the material making up said sheet 2 allows the surgicalinstrument 1, when it is in its flat spiral configuration shown in FIG.5, to be folded in half on itself under the effect of a pressure exertedon two opposite edges, for example according to a fold corresponding toone of its diameters: in such a case, due to the resilience of the sheet2, the surgical instrument 1 tends to return naturally to its flatconfiguration when the exerted pressure is released.

The disc or surgical instrument 1 thus has properties of resilience(redeployment after folding), rigidity (maintenance of the prosthesisagainst the abdominal wall), flexibility (facilitating removal thereof):the surgical instrument 1 according to the invention also plays aprotective role, as will appear later, in the area of the seam 205 ofthe prosthesis, during fixing of the latter to the abdominal wall,against any perforations by the suture needles or the staplerinsertions.

As appears in FIG. 6, the upper end 3 a of the spiral (or disc) 3comprises a removal tab 4.

The surgical instrument 1 can be introduced extremely easily into aprosthesis 200 as shown in FIG. 2: indeed, to do so, one need only, byusing the spiral 3 of the sheet 2 in its deployed form as shown in FIG.6, introduce the lower end 3 b of the spiral 3 into the opening 204 ofthe prosthesis, then rotate the spiral 3 relative to the prosthesis 200by making the sheet 2 slide in the inner space 203 of the prosthesis200.

Preferably, the material making up the sheet 2 has a low frictioncoefficient relative to the prosthesis 200 to facilitate both itsintroduction into the prosthesis 200, and as will be seen later, itsremoval. For example, if the threads making up the prosthesis are madefrom polyester, or polypropylene, and the sheet 2 is made frompolypropylene, or polytetrafluoroethylene, the sheet 2 will slide easilyagainst the prosthesis 200 because polyester and polypropylene have alow friction coefficient relative to polypropylene andpolytetrafluoroethylene.

In this way, the sheet 2 can be introduced completely into the innerspace 203 of the prosthesis 200, as shown in FIG. 7. As appears in thatfigure, once the surgical instrument 1 is completely introduced into theprosthesis 200, the spiral 3 is replaced in its flat configuration(corresponding to FIG. 5), with the removal tab 4, situated at the upperend 3 a of the spiral 3, visible through the opening 204.

The kit 10 thus made up of the prosthesis 200 and the surgicalinstrument 1 completely introduced into the open space 203 of theprosthesis 200, is completely flat. Due to the resilience of the sheet 2forming the surgical instrument 1 and the natural flexibility of theprosthesis 200, the layers (201, 202) of which are arrangements ofthreads, the surgeon can grasp the kit 100 (prosthesis 200+instrument 1)and fold it in two, or even in four, as shown in FIG. 8, by exertingpressure on the edges of the kit 10 in order to introduce it into theimplantation site in the abdominal cavity 109 through the incisionsformed at the skin 108 and the fascia 102. Because it is folded onitself, the kit 10 takes up little space and is easily introduced intosmall incisions.

Once in the abdominal cavity 109, the kit 10 redeploys naturally, owingto the resilience of the sheet 2, which tends to return naturally to itsflat spiral position 3 (corresponding to FIG. 5). FIG. 9 shows the kit10, as redeployed in the abdominal cavity: in this figure, however, forclarity reasons, the implantation site has not been shown again. Owingto the presence of the surgical instrument 1, its shape and itsstructure, and in particular its resilient properties, the surgeon thenknows that the prosthesis 200 is completely deployed, and that its layer201 in particular is advantageously pressed against the fascia 102 ofthe abdominal wall, without forming folds that risk causing unfortunatesutures with fragile surrounding organs such as the viscera. The surgeoncan then suture the layer 201 of the prosthesis 200 to the fascia 102 ofthe abdominal wall, using a needle 11 and thread 12 for example, asshown in FIG. 9. He thus performs the sutures 903 shown in FIG. 4, onthe periphery of the prosthesis 200, thereby forming fastening means forfastening the prosthesis 200. Alternatively, the surgeon could use astapler, for example a laparoscopy stapler, and staples as fasteningmeans. During this operation, the surgical instrument 1 according to theinvention plays a protective role to protect the surrounding viscera, inparticular in the vicinity of the seam 205 of the prosthesis 200, byavoiding, due to the presence of the sheet 2 that forms a barrier, anyperforations of these viscera by the suture needles or the insertions bythe stapler.

During this operation, the surgeon can be assisted, to center the kit10, and therefore the prosthesis 200, on the defect to be filled in, bycentering threads 13, already bound, or that he has bound beforehand, tothe prosthesis 200 on the perimeter of the opening 204 thereof, as shownin FIG. 9. These centering threads 13 are preferably removed once theprosthesis 200 is attached.

Once the prosthesis 200 is thus attached, the surgeon can remove thesurgical instrument 1, by removing the prosthesis 200 through theopening 204: to that end, he pulls on the sheet 2 using the removal tab4, which he grasps easily through the opening 204, and he deploys thespiral 3 while making it rotate relative to the prosthesis 200, as shownin FIG. 10. The surgical instrument 1 is thus easily removed from theprosthesis 200, in particular when the friction coefficient of thematerial making up the sheet 2 is low relative to the prosthesis 200.

The surgeon then needs only close the initial incisions of the fascia102 and the skin 106 using sutures 901 as shown in FIG. 4.

The surgical instrument 1 according to the invention thus allows adeployment and spreading out of the prosthesis 200 that are as effectiveas possible during an operation to reduce a hernial defect. Inparticular, due to its spring effect and its ability to stiffen theprosthesis, the surgical instrument according to the invention makes itpossible both to reduce the space occupied by the prosthesis when it isintroduced into the implantation site, and to perform optimal pressingof the latter against the abdominal wall, thereby making it possible toavoid the formation of unwanted folds within the prosthesis.

The present invention also pertains to a method for treating orpreventing a hernia in the umbilical region, by using a prosthesis and asurgical instrument (or disc) as described above and comprising thefollowing steps:

One has a prosthesis and a surgical instrument (or disc or spiral) asdescribed above: in one embodiment of the invention, the disc, in itsflat configuration, is already housed in the prosthesis; in anotherembodiment, the surgeon introduces the disc, in its flat form, insidethe prosthesis: the latter is thus completely deployed and slightlystiffened by the sheet of material making up the disc;

An incision is made on the abdominal wall at the hernial defect;

After treating the hernia, said prosthesis, in which the disc is housed,is inserted into the incision by folding it by exerting pressure on theedges of the disc;

Owing to its spring effect, the disc deploys in the abdominal cavity,bringing about the spreading out of the prosthesis; said prosthesis ispositioned against the abdominal wall, centering it on the defect, forexample by pulling on the centering threads of the prosthesis, the sheetof material of the disc stiffening the prosthesis and pressing itagainst the abdominal wall such that viscera are prevented from beinginserted between said prosthesis and the abdominal wall; a correctspreading out of said prosthesis is thus ensured;

The prosthesis is fixed against the abdominal wall owing to fasteningmeans;

One then pulls on the removal tab situated at the upper end of thespiral of the disc; in so doing, one deploys the spiral and removes thedisc by making it rotate slowly around itself.

1-9. (canceled)
 10. A surgical instrument for deploying a prosthesisintended to fill-in a hernial defect of the abdominal wall, saidprosthesis comprising: at least one first layer made from abiocompatible flexible material intended to be placed opposite theabdominal wall, and at least one second layer made from a biocompatibleflexible material intended to be placed opposite the abdominal cavity,said first and second layers being assembled together so as to define aninternal space accessible to said surgical instrument by means of anopening provided in said first layer, said surgical instrumentcomprising at least one sheet made of a flexible resilient material,said sheet continuously overlapping itself one or more times so as todefine a plurality of levels forming a spiral.
 11. The surgicalinstrument according to the claim 10, characterized in that said spiralis able to adopt a substantially flat configuration, in which each levelis in contact with an adjacent level, corresponding to an idleconfiguration in which the spiral does not undergo significant stresses,or on the contrary a deployed configuration, in which no level is incontact with another level, corresponding to a configuration in which aforce tending to space the two ends of the spiral away from each otheris exerted.
 12. The surgical instrument according to claim 10,characterized in that the upper end of the spiral comprises a removaltab.
 13. The surgical instrument according to claim 10, characterized inthat the material making up said sheet is a polymer chosen frompolypropylene, polyethylene, polytetrafluoroethylene, and mixturesthereof.
 14. A surgical kit for treating a hernia of the abdominal wallcomprising: a surgical instrument according to claim 10 and a prosthesisintended to fill in said defect, said prosthesis comprising at least onefirst layer of a biocompatible flexible material intended to be placedopposite the abdominal wall and at least one second layer ofbiocompatible flexible material intended to be placed opposite theabdominal cavity, said first and second layers being assembled to eachother so as to define an open inner space open using an opening formedin said first layer.
 15. The surgical kit according to claim 14,characterized in that it includes a plurality of centering threadsintended to be connected to said prosthesis around the perimeter of saidopening.
 16. The surgical kit according to claim 14, characterized inthat at least one of the layers of said prosthesis is made up of anarrangement of threads.
 17. The surgical kit according to claim 17,characterized in that both layers are made up of an arrangement ofthreads.
 18. The surgical kit according to claim 14, characterized inthat the second layer of said prosthesis of the kit is covered with ananti-adhesive coating on a face of the second layer intended to beplaced opposite the abdominal cavity.